1. Field of the Invention
The present invention relates to a semiconductor device of the type which has a plurality of terminals in a bonding area for electrical connection to a corresponding number of bonding pads on a printed circuit board.
2. Description of the Related Art
In general, a semiconductor device of the above described type includes a semiconductor chip such as an IC chip having a mounting surface provided with a plurality of electrode pads along the edges of the chip mounting surface, and an intermediary buffer board attached to the mounting surface of the chip. The buffer board has a matrix of terminals and a wiring pattern for electrically connecting the electrode pads of the chip to the respective terminals of the buffer board.
In use, the semiconductor device is mounted on a printed circuit board in a manner such that the matrix of terminals of the buffer board comes into contact with a corresponding matrix of bonding pads on the printed circuit board. Each of the terminals of the buffer board may be a solder bump which fuses under heating to a corresponding one of the bonding pads on the printed circuit board. The buffer board absorbs or allows for a linear expansion difference between the semiconductor chip and the printed circuit board when heated for soldering, so that the semiconductor chip is prevented from being damaged due to such an expansion difference.
In production, use is made of a master buffer board which is cut into a plurality of unit buffer boards for making a corresponding number of semiconductor devices. However, since the master buffer board needs to be provided with a specific wiring pattern for each of the unit buffer boards, the same master buffer board cannot be used for preparing a plurality of unit buffer boards suitable for different types of semiconductor chips. In other words, a different master buffer board must be used for each different type of semiconductor device, which results in a production cost increase.